void
readHeader (const char fileName[])
{
    RgbaInputFile file (fileName);

    const StringAttribute* comments =
        file.header ().findTypedAttribute<StringAttribute> ("comments");

    const M44fAttribute* cameraTransform =
        file.header ().findTypedAttribute<M44fAttribute> ("cameraTransform");

    if (comments) cout << "commentsn " << comments->value () << endl;

    if (cameraTransform)
        cout << "cameraTransformn" << cameraTransform->value () << flush;
}
